期刊文献+
共找到47,231篇文章
< 1 2 250 >
每页显示 20 50 100
A Cognitive Study on Politeness Intention Processing and Its Association with Pragmatic Failure in Cross-Cultural Communication
1
作者 Rong YAN Tengfei FENG Samad ZARE 《Chinese Journal of Applied Linguistics》 2024年第3期481-497,525,共18页
Although a large number of studies have focused on various aspects of politeness,very little is known about how politeness intention is activated cognitively during verbal communication.The present study aims to explo... Although a large number of studies have focused on various aspects of politeness,very little is known about how politeness intention is activated cognitively during verbal communication.The present study aims to explore the cognitive mechanism of politeness intention processing,and how it is related to pragmatic failure during cross-cultural communication.Using 30 Chinese EFL university students who were instructed to finish a probe word judgment task with 96 virtual scenarios,the results indicate that within both mono-and cross-cultural contexts,the response time in the experimental scenarios was significantly slower than that of the filler scenarios.This suggests that politeness intention was activated while understanding the surface meaning of the conversation;however,the EFL learners could not completely avoid the negative transfer of their native politeness conventions when they were comprehending the conversational intention of the target language.Furthermore,no significant differences in response time were found between the groups with high and low English pragmatic competence,illustrating that transferring the pragmatic rules and principles into cross-cultural communication skills was more cognitively demanding.Overall,this study adds to the literature on politeness research and provides some implications for foreign language pragmatic instructions. 展开更多
关键词 politeness intention cognitive processing pragmatic failure cross-cultural pragmatics cross-cultural communication
下载PDF
A Comparative Study of the L2 Pragmatic Competence of University Students in Hong Kong and the Chinese Mainland:The Contributions of Sociocultural Context and Linguistic Proficiency
2
作者 Scott AUBREY Rod ELLIS 《Chinese Journal of Applied Linguistics》 2024年第3期371-392,524,共23页
This study investigates the differences in pragmatic competence between Hong Kong and Chinese mainland university students.Participants included 19 native speakers of English,115 Chinese mainland students,divided into... This study investigates the differences in pragmatic competence between Hong Kong and Chinese mainland university students.Participants included 19 native speakers of English,115 Chinese mainland students,divided into those who had spent time abroad in an English-speaking country(CM A)and those who had not(CM NA),and 97 Hong Kong students,divided into those from an English-medium secondary school(Hong Kong EMI)and those from a Chinese-medium school(Hong Kong CMI).Linguistic proficiency was measured by a C-test,and pragmatic competence by a Metapragmatic Knowledge Test,an Irony Test and a Monologic Role Play.Group scores were compared using ANCOVAs to control for differences in proficiency.The results point to a continuum of pragmatic competence—EMI>CMI>CM A>CM NA—reflecting the groups’access to English in real-life contexts.The differences between the Hong Kong groups and the Chinese mainland groups were clearest in those tests measuring processing capacity(i.e.,Irony Response Time and the Monologic Role Play).CM A,but not CM NA,performed as well as the Hong Kong groups on measures of metapragmatic awareness.The results are discussed in terms of Bialystok’s(1993)distinction between analyzed representation and control of processing. 展开更多
关键词 pragmatic competence social context Hong Kong the Chinese mainland metapragmatic knowledge processing capacity
下载PDF
English Translation of Public Signs in Chinese from a Pragmatic Perspective
3
作者 YANG Chen-min GAO Wen-cheng 《Journal of Literature and Art Studies》 2024年第10期854-860,共7页
This paper applies Newmark’s communicative translation and semantic translation theory to analyzing the English translation of Chinese public signs and its pragmatic functions. It finds that communicative translation... This paper applies Newmark’s communicative translation and semantic translation theory to analyzing the English translation of Chinese public signs and its pragmatic functions. It finds that communicative translation is typically used to fulfill the communicative function of public signs. Both communicative and semantic translation are employed to adapt to different situational contexts, in order to preserve the pragmatic functions of the Chinese public signs. The differences between Chinese and English lead to pragmatic errors in translation, making the translator’s bilingual proficiency and familiarity with English culture necessary. The fundamental principle of public sign translation is to be concise and clear, which often requires modifying some complex rhetorical devices from Chinese in translation. 展开更多
关键词 public sign Chinese-English translation pragmatic analysis
下载PDF
Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier
4
作者 Jean Fidele Nzihou Salou Hamidou +2 位作者 Ousmane Zoundi Frederic Ouattara Bila Gerard Segda 《Open Journal of Applied Sciences》 2024年第2期545-560,共16页
The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and... The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio. 展开更多
关键词 equivalence Ratio Biomass GASIFICATION Lambda Sensor MICROCONTROLLER C++
下载PDF
From“Semantic Equivalence”to“Verve Reproduction”—Exploration on Xu Yuanchong’s English Translation of the Analects
5
作者 GUO Junyi 《Cultural and Religious Studies》 2024年第7期434-442,共9页
This paper focuses on the English translation of Xu Yuanchong’s Analects,explains in depth the theory of semantic equivalence and the theory of verve reproduction.It analyzes the application and integration of these ... This paper focuses on the English translation of Xu Yuanchong’s Analects,explains in depth the theory of semantic equivalence and the theory of verve reproduction.It analyzes the application and integration of these two theories by Xu Yuanchong in detail.Through a comprehensive textual analysis,this paper summarizes the remarkable achievements of the English translation of the Analects,such as the accurate transmission of semantics and the vivid reproduction of cultural charm,which is expected to bring new thinking directions and valuable references to the study of the English translation of the Analects. 展开更多
关键词 semantic equivalence verve reappeared Xu Yuanchong English translation of the Analects
下载PDF
Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
6
作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 Special Relativity’s Hyperbolic Versus Circular Versions Galilean Kinematics Partial equivalence of SR and Newton’s Theories Algebra of Relativistic and the Corresponding Galilean Velocities
下载PDF
Pragmatic Equivalence in Different Translations of The Merchant of Venice
7
作者 白婕 《海外英语》 2015年第23期249-251,共3页
Pragmatic equivalence, meaning to transfer the implied meaning of the source text to the target text, usually involves the receiver to whom the translation is directed. Two notions are crucial in translation to achiev... Pragmatic equivalence, meaning to transfer the implied meaning of the source text to the target text, usually involves the receiver to whom the translation is directed. Two notions are crucial in translation to achieve pragmatic equivalence: context and optimal relevance. In light of these two element, the author in this paper conducts a case study by using Shakespeare's play The Merchant of Venice and two Chinese versions from Zhu Shenghao and Sun Dayu as data, by comparing these two versions to explore how pragmatic equivalence in translation can be achieve at lexical, semantic and cultural levels. 展开更多
关键词 pragmatic equivalence TRANSLATION The MERCHANT of VENICE
下载PDF
The Application of Pragmatic-Markedness Equivalence Principle in the Translation of Tourist Publicity Materials
8
作者 陈志海 DONG Shu-xin ZHOU Xuan 《海外英语》 2015年第6期116-118,共3页
Chinese tourism becomes a thriving field with the promotion of China reform and opening policy and the rapid development of social economy. The translation of tourist materials thus weighs a lot in the economic develo... Chinese tourism becomes a thriving field with the promotion of China reform and opening policy and the rapid development of social economy. The translation of tourist materials thus weighs a lot in the economic development and cross-cultural communication. But the condition is not satisfactory, there are still existing some problems in the translation of tourist publicity materials. Therefor the readers can't receive the equal information that the original text expressed. Based on this fact,the paper attempts to analyze what pragmatic failures there are in the translation of tourist materials and to analyze how the Pragmaticmarkedness Equivalence Principle(PMEP) approach can be applied to the translation of tourist publicity materials to achieve the translation equivalence. 展开更多
关键词 TOURIST PUBLICITY materials MARKEDNESS TRANSLATION pragmatic-markedness equivalence TRANSLATION
下载PDF
Effectiveness of an amino acid beverage formulation in diarrheapredominant irritable bowel syndrome:A pragmatic real-world study 被引量:1
9
作者 Samantha E Niles Phil Blazy +5 位作者 Samuel N Cheuvront Robert W Kenefick Sadasivan Vidyasagar Adam BSmith Neil Fawkes William Denman 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 2023年第5期39-49,共11页
BACKGROUND Amino-acid based medical foods have shown promise in alleviating symptoms of drug induced gastrointestinal side effects;particularly,diarrhea-predominant symptoms.Irritable bowel syndrome(IBS)is a gastroint... BACKGROUND Amino-acid based medical foods have shown promise in alleviating symptoms of drug induced gastrointestinal side effects;particularly,diarrhea-predominant symptoms.Irritable bowel syndrome(IBS)is a gastrointestinal disorder that affects up to 9% of people globally,with diarrhea predominant IBS(IBS-D)being the most prevalent subtype.Further trials are needed to explore potential added benefits when integrated into standard care for IBS-D.AIM To assess the effectiveness of an amino acid-based medical food as an adjunct to standard of care for adults with IBS-D.METHODS This is a pragmatic,real world,open label,single arm study comparing a 2-week baseline assessment to a 2-week intervention period.One hundred adults,aged 18 to 65 years,with IBS-D,according to Rome IV criteria,were enrolled after completing a 2-week baseline assessment period and received a 2-week supply of an amino acid based medical food which was consumed at home twice daily on top of their standard of care.The primary outcome was an assessment of tolerability after 2-weeks of consumption,while secondary outcomes included changes in stool consistency(Bristol Stool Form Scale),severity of abdominal pain&discomfort,symptoms of urgency,Global Improvement Survey(GIS),and the IBS severity scoring system(IBS-SSS).RESULTS The test product was well-tolerated as each participant successfully completed the full 14-day trial,and there were no instances of dropouts or discontinuation of the study product reported.Forty percent of participants achieved a 50% or more reduction in the number of days with type 6-7 bowel movements(IBS-D stool consistency responders).Fifty-three percent of participants achieved a clinically meaningful reduction of 30% in mean weekly pain scores,and 55%experienced the same for mean weekly discomfort scores(IBS-D pain and discomfort responders).Participants experienced a mean-109.4(95% confidence interval:-130.1,-88.8)point reduction on the IBS-SSS and 52% experienced a minimally clinically important difference of>95 points.An IBS-SSS category shift from severe to moderate or mild occurred in 69% of participants.For functional symptoms,76% of participants reported symptom relief on the GIS.CONCLUSION The amino acid-based medical food was well-tolerated,when added to the standard of care,and demonstrated improvements in both overall IBS symptom severity and IBS-D symptoms within just 2 wk. 展开更多
关键词 Diarrhea-predominant irritable bowel syndrome Amino acid beverage formulation pragmatic real-world study Medical food Bristol Stool Form Scale Irritable Bowel Syndrome–Severity Scoring System
下载PDF
Exploration of Cross-Cultural Pragmatic Failures in English Interpretation and Their Solutions
10
作者 MA Yanling 《Sino-US English Teaching》 2023年第5期165-170,共6页
From the perspective of international market development and international cultural exchange,English is the main applied language,especially in most western countries.With the deepening of global economic integration ... From the perspective of international market development and international cultural exchange,English is the main applied language,especially in most western countries.With the deepening of global economic integration and international trade,cultural collisions are becoming increasingly frequent,and interpretation in different languages is inevitably required.However,interpretation does not only mean transfer language,it also involves culture.In the practice of interpretation,some errors arise from the lack of cross-cultural awareness,which becomes pragmatic errors.Therefore,this article will mainly discuss cross-cultural pragmatic failures in English interpretation with some examples and specific solutions.Firstly,it will introduce what pragmatic failures are and typical types of failures,clarify the relationship between English interpretation and pragmatic failures,and then elaborate on representative cross-cultural pragmatic failures in English interpretation.Finally,it will summarize the reasons and solutions that lead to cross-cultural pragmatic failures in English interpretation,putting forward corresponding suggestions for reducing cross-cultural pragmatic failures. 展开更多
关键词 English interpretation cross cultural pragmatic failure SOLUTIONS
下载PDF
Promoting the International Dissemination of Chinese Culture Through International Chinese Language Education: A Case Study of Chinese-English Idiomatic Equivalence
11
作者 Jia Fengrong 《Contemporary Social Sciences》 2023年第6期119-140,共22页
One major task of our improvement of China’s international communication capabilities is to tell China’s stories well and make China’s voice heard to communicate a comprehensive,multi-dimensional view of China in t... One major task of our improvement of China’s international communication capabilities is to tell China’s stories well and make China’s voice heard to communicate a comprehensive,multi-dimensional view of China in the international arena.International Chinese language education bears the dual responsibility of spreading the Chinese language and promoting the Chinese culture.How to shape global narratives for telling China’s stories and improve China’s international communication capabilities has become an important issue that concerns international Chinese language education.Chinese idioms,which are hidden treasures of the Chinese language,can play a unique role in this regard.It is therefore necessary to review the content and methods of including idioms in international Chinese language education.In this paper,instruction in idioms is approached by making a corpus-based comparative analysis from the theoretical perspectives of equivalence,cognitive metaphor,and second language acquisition.Qualitative and quantitative methods are combined to analyze idioms to be added to the vocabulary of international Chinese language education in three dimensions:word frequency,semantic transparency,and functional equivalence.This paper aims to explore a new approach to the dissemination of Chinese culture through instruction in idioms in international Chinese language education. 展开更多
关键词 international Chinese language education IDIOMS word frequency semantic transparency functional equivalence international communication capabilities
下载PDF
A Physical Interpretation of Mass-Energy Equivalence Based on the Orthogonal Collision
12
作者 Weihong Qian 《Journal of Modern Physics》 2023年第7期1067-1086,共20页
Einstein described the mass-energy equivalence as the most important result of special relativity. But more than a century after Einstein first derived the relationship between mass-energy equivalence (or mass-energy ... Einstein described the mass-energy equivalence as the most important result of special relativity. But more than a century after Einstein first derived the relationship between mass-energy equivalence (or mass-energy equation), questions left for people are how to understand that mass and energy are somehow equivalent, and how to give the dynamical process for the conversion from mass to energy (or vice versa). This paper first interprets the formula of mass-energy equivalence published by Einstein in 1905, and then gives the equivalence relationship of mass-energy transition based on the dynamics of particle orthogonal collision. As a result, the orthogonal collision of two high-energy mass particles can generate a huge mass-energy density, equivalent to the total energy of N new particles, which is a one-way dynamic process that generates new mass-energy density and new matter. This conversion of mass into energy has nothing to do with special relativity. 展开更多
关键词 Mass-Energy equivalence Orthogonal Collision Physical Interpretation Dynamical Process Special Relativity
下载PDF
Theoretical Transplantation into Translation Studies——An Analysis on the Pragmatic Application of Hofstede’s
13
作者 ZHANG Zhi-chao WANG Guo-nian 《Journal of Literature and Art Studies》 2023年第7期514-521,共8页
The deepening process of globalization has given rise to restless cultural exchanges among people from different regions of the world through newspapers,books,and other written media.However,the significant difference... The deepening process of globalization has given rise to restless cultural exchanges among people from different regions of the world through newspapers,books,and other written media.However,the significant differences in languages and cultures have become an insurmountable gap in intercultural communication.To lubricate cultural exchanges,new translation theories that focus on the transformation of different cultural concepts shall be introduced and adopted.This paper aims to extract applicable notions from Hofstede’s Cultural Dimensions for pragmatic translation studies by laying emphasis on its pragmatic value through case study.By such theoretical transplantation,valuable suggestions are proposed to tackle cultural misunderstandings and conflicts encountered amid cultural exchanges. 展开更多
关键词 cultural exchange Hofstede’s Cultural Dimensions pragmatic translation studies theoretical transplantation
下载PDF
基于结构响应的舱室内爆TNT等效方法 被引量:1
14
作者 周沪 孔祥韶 +3 位作者 罗峰 曹宇航 郑成 吴卫国 《中国舰船研究》 CSCD 北大核心 2024年第3期86-95,共10页
[目的]旨在揭示爆轰产物后燃烧效应对封闭空间中爆炸载荷的影响规律。[方法]通过往封闭舱室中充入氮气来抑制爆轰产物燃烧,开展在空气和氮气两种不同气体环境下封闭舱室内TNT爆炸响应试验,记录温度、压力变化历程和靶板中心点残余挠度,... [目的]旨在揭示爆轰产物后燃烧效应对封闭空间中爆炸载荷的影响规律。[方法]通过往封闭舱室中充入氮气来抑制爆轰产物燃烧,开展在空气和氮气两种不同气体环境下封闭舱室内TNT爆炸响应试验,记录温度、压力变化历程和靶板中心点残余挠度,建立基于无量纲载荷参数的靶板变形与炸药释放能量之间的关系,并提出考虑后燃烧效应的封闭空间TNT等效方法。[结果]结果发现,由于爆轰产物燃烧能量释放量不同,在氮气环境中,封闭空间内爆炸压力、温度和靶板动态响应明显低于空气环境。内爆载荷分析需计入TNT爆炸产物燃烧释放的能量及其增强效应。[结论]与现有基于准静态压力的TNT当量计算方法进行的比较表明,所提基于结构响应的舱室内爆TNT等效方法具有合理性和良好的适用性。 展开更多
关键词 封闭爆炸载荷 后燃烧效应 TNT当量
下载PDF
城乡等值化视角下旅游驱动乡村治理的理论逻辑与作用机制 被引量:3
15
作者 刘民坤 邓小桂 +1 位作者 任莉莉 梁连健 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期94-102,共9页
乡村旅游是乡村振兴的重要路径,而乡村治理又是乡村振兴的核心内容.通过旅游驱动乡村治理已在实践层面和理论研究中受到持续关注,但是对其理论逻辑和作用机制的探究还有待深化.该文基于城乡等值化视角,分析旅游驱动城乡要素流动改善乡... 乡村旅游是乡村振兴的重要路径,而乡村治理又是乡村振兴的核心内容.通过旅游驱动乡村治理已在实践层面和理论研究中受到持续关注,但是对其理论逻辑和作用机制的探究还有待深化.该文基于城乡等值化视角,分析旅游驱动城乡要素流动改善乡村治理的理论逻辑和作用机制.研究发现:1)乡村旅游能够打破乡村治理的边界,桥接城乡要素的流动,通过促进城乡要素的双向循环流动来推动乡村治理;2)在城乡等值化背景下,乡村旅游通过调整土地、人才、资本、文化、生态、技术等城乡要素的流动状态,在乡村治理层面形成响应,进而助推达成乡村经济、社会、文化、生态、政治等多元治理目标;3)应根据乡村旅游发展实际,将其置于城乡协调发展的整体框架下,旅游驱动乡村治理的积极贡献才能最大地发挥出来. 展开更多
关键词 城乡等值 乡村旅游 乡村治理 理论逻辑 作用机制
下载PDF
计及低电压穿越及故障全过程动态的双馈风电场等值方法 被引量:1
16
作者 周海强 崔晓丹 +3 位作者 许剑冰 曹博源 高超 陈志昊 《电力系统自动化》 EI CSCD 北大核心 2024年第6期216-225,共10页
在分析双馈感应发电机(DFIG)故障各阶段动态的基础上,提出了一种计及低电压穿越控制的双馈风电场等值方法。首先,讨论了低电压穿越控制策略,给出了含双馈风电场的电力系统故障稳态潮流计算方法。在考虑电压暂态过程的条件下,分析了外部... 在分析双馈感应发电机(DFIG)故障各阶段动态的基础上,提出了一种计及低电压穿越控制的双馈风电场等值方法。首先,讨论了低电压穿越控制策略,给出了含双馈风电场的电力系统故障稳态潮流计算方法。在考虑电压暂态过程的条件下,分析了外部系统短路故障后DFIG转子电流的变化机理,指出电压跌落深度及风电功率是影响短路电流的主要因素,可根据动作分界线判断撬棒是否动作。然后,根据初始风速及撬棒状态将风电场中的DFIG分为3群,并对等值DFIG及集电网络进行聚合。为提高等值模型在恢复阶段的精度,根据故障稳态电压对双馈风电场功率恢复曲线进行预估,并在此基础上对等值DFIG恢复速率进行分段修正。最后,对含双馈风电场的算例系统进行了等值计算。仿真结果表明,等值模型较好地保持了原系统在故障各阶段的动态,在保持较高精度的前提下有效简化了系统,提高了计算速度。 展开更多
关键词 双馈感应发电机 风电场 低电压穿越 电力潮流 撬棒 动态等值 等值模型 功率恢复
下载PDF
罗蒂的新实用主义及其与后现代主义的关系 被引量:1
17
作者 张庆熊 《哲学分析》 CSSCI 北大核心 2024年第3期43-52,197,共11页
罗蒂与后现代主义的关系相当复杂。罗蒂通过批判欧洲近代哲学的“表象论”的认识论路线和早期分析哲学的“图像论”语言观而得出某些类似于后现代主义的结论。从这一角度看,罗蒂与法国后现代主义代表人物德里达一样都致力于解构形而上... 罗蒂与后现代主义的关系相当复杂。罗蒂通过批判欧洲近代哲学的“表象论”的认识论路线和早期分析哲学的“图像论”语言观而得出某些类似于后现代主义的结论。从这一角度看,罗蒂与法国后现代主义代表人物德里达一样都致力于解构形而上学。然而,罗蒂的实用主义立场又导致他在文化观等方面与法国后现代主义者分道扬镳。罗蒂从实用的效果出发肯定现代性和世俗社会中的某些积极因素,并且他还为技术理性、人本主义和怀抱希望的浪漫主义精神正名,批评后现代主义一味解构和不提出任何致力于改造社会的理想蓝图。至于罗蒂的新实用主义究竟新在何处和有无问题,可将其与传统的实用主义论点和后现代主义的论点相对照。 展开更多
关键词 罗蒂 新实用主义 后现代主义 技术理性 文化政治
下载PDF
基于电路等效的并网逆变器失稳分析与稳定控制 被引量:2
18
作者 高磊 吕敬 +2 位作者 马骏超 刘佳宁 蔡旭 《电工技术学报》 EI CSCD 北大核心 2024年第8期2325-2341,共17页
以并网逆变器为功率接口的新能源发电系统在弱电网条件下易发生振荡失稳问题。该文将并网逆变器的控制回路可视化为电路元件组成的虚拟阻抗,基于该电路模型分析了弱电网条件下电流内环与锁相环交互作用导致并网逆变器振荡失稳的机理,在... 以并网逆变器为功率接口的新能源发电系统在弱电网条件下易发生振荡失稳问题。该文将并网逆变器的控制回路可视化为电路元件组成的虚拟阻抗,基于该电路模型分析了弱电网条件下电流内环与锁相环交互作用导致并网逆变器振荡失稳的机理,在此基础上,提出了基于有源阻尼的稳定控制设计方法,并对不同有源阻尼控制的电路特性以及稳定性提升能力进行了对比分析。研究结果表明,针对锁相环引入负电阻造成的振荡失稳问题,阻抗-高通滤波器型有源阻尼控制策略具有更优的稳定性提升能力。最后通过PSCAD/EMTDC仿真和远宽StarSim控制器硬件在环实验对比了不同有源阻尼控制策略的振荡抑制效果,并验证了阻抗-高通滤波器型有源阻尼控制的动态性能。结果表明,所设计的稳定控制能够在200 ms内有效抑制系统振荡,并且可实现在短路比为1的极弱电网条件下稳定运行。 展开更多
关键词 并网逆变器 电路等效 振荡稳定性 有源阻尼 虚拟阻抗 稳定控制
下载PDF
无刷双馈电机研究综述与展望 被引量:3
19
作者 于克训 陈曦 +2 位作者 谢贤飞 赵探探 潘卫东 《电工技术学报》 EI CSCD 北大核心 2024年第2期397-422,共26页
无刷双馈电机具有结构可靠、变频器容量小等优势,非常适合灵活运行于防爆、易燃等特殊或极端工况,近年来受到广泛关注。该文根据无刷双馈电机的基本工作原理,明确了该类电机的命名原则与规范名称;总结了现有定转子方案的结构及性能特点... 无刷双馈电机具有结构可靠、变频器容量小等优势,非常适合灵活运行于防爆、易燃等特殊或极端工况,近年来受到广泛关注。该文根据无刷双馈电机的基本工作原理,明确了该类电机的命名原则与规范名称;总结了现有定转子方案的结构及性能特点,综合考虑性能指标与结构工艺,提出了转子双套绕组的发展方向;梳理了无刷双馈电机的稳态等效电路模型及基于各类数学模型的优化设计方法,针对现存难以完整考虑不同转速工况性能的不足,阐明了利用新型同步-异步相串联等效电路进行优化设计的思路;对比分析了经典及新近出现的无刷双馈电机控制系统拓扑和控制策略特点,面向典型电动、发电工况建立了完整的电机及控制系统。最后,对无刷双馈电机的上述理论研究问题及工业应用的发展方向进行了总结阐述,为该类电机的深入研究及加快推广应用提供参考和指导。 展开更多
关键词 无刷双馈电机 命名原则 定转子方案 等效电路 优化设计 控制系统
下载PDF
CMIP6模式对欧亚大陆冬季雪水当量的模拟能力评估及未来预估 被引量:1
20
作者 陈红 史学丽 《气候与环境研究》 CSCD 北大核心 2024年第1期75-89,共15页
基于第六次耦合模式比较计划(CMIP6)的模式模拟数据和欧洲宇航局GlobSnow卫星遥感雪水当量(Snow Water Equivalent,SWE)资料,评估了CMIP6耦合模式对1981~2014年欧亚大陆冬季SWE的模拟能力,并应用多模式集合平均结果预估了21世纪欧亚大陆... 基于第六次耦合模式比较计划(CMIP6)的模式模拟数据和欧洲宇航局GlobSnow卫星遥感雪水当量(Snow Water Equivalent,SWE)资料,评估了CMIP6耦合模式对1981~2014年欧亚大陆冬季SWE的模拟能力,并应用多模式集合平均结果预估了21世纪欧亚大陆SWE的变化情况。结果表明,CMIP6耦合模式对冬季欧亚大陆中高纬度SWE空间分布具有较好的再现能力,能模拟出欧亚大陆中高纬度SWE的主要分布特征;耦合模式对SWE变化趋势及经验正交函数主要模态特征的模拟能力存在较大差异,但多模式集合能提高模式对SWE变化趋势和主要时空变化特征的模拟能力;此外,多模式集合结果对欧亚大陆冬季SWE与降水、气温的关系也有较好的再现能力。预估结果表明,21世纪欧亚大陆东北大部分地区的SWE均要高于基准期(1995~2014年),而90°E以西的欧洲大陆SWE基本上呈现减少的特征;21世纪早期,4种不同排放情景下积雪变化的差异不大,但21世纪后期积雪变化的幅度差异较大,而且排放越高积雪变化的幅度越大,模式不确定性也越大;进一步的分析表明,欧亚大陆冬季未来积雪变化特征的空间分布与全球变化背景下局地气温、降水的变化密切相关,高温高湿的条件有利于欧亚大陆东北部积雪的增多。 展开更多
关键词 欧亚大陆雪水当量 CMIP6 模式 冬季 模拟 预估
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部